The present invention relates to a securing system for a conventional doorjamb strike plate, and more particularly relates to a device which provides greater strength for a strike plate mounted in a door frame jamb structure.
In recent years, greater attention has been given to providing increased security to homes against unauthorized entry. For example locks have been made with longer and heavier bolts in order to provide increased security. The security actually realized with such locks however has been limited because the lock bolt is commonly received in a strike or keeper plate mounted on or in a relatively weak wooden doorjamb which can be broken apart by a moderate blow to the door.
While it is known to provide strikes of larger size having more screws and made of thicker metal to replace the common strike, many of these devices require the screws to be set into this same relatively weak wood. Again the system can still be broken apart by a moderate blow to the door. Excessive remodelling, if not replacement of the frame jamb altogether because of the weakness, would be required.
Moreover, many of these devices require screws to be set into wood at right angles to the strike body. Because the grain in wood usually runs vertically within the door frame parallel with the vertical line of the strike plate mounting screws, any lateral stress applied to these screws tends to concentrate in a way that splits the wood along this weaker plane.
Attempts have been made to strengthen conventional strike plates. For example, Hansen U.S. Pat. No. 4,211,442 issued July 8, 1980, and Detlefs U.S. Pat. No. 4,186,954 issued Feb. 5, 1980, describe and illustrate strike plate assemblies in which extensions or brace members projecting perpendicularly to the plane of the main body of the strike plate, extend behind it into the adjoining wall support, thereby providing greater security against displacement of the strike plate. Payne U.S. Pat. No. 2,533,396 issued Dec. 12, 1950 describes and illustrates a further construction of strike plate, this one being of a construction which is releasable by a person on one side of the door frame so that that person may disassemble the strike plate if for instance that person is locked in. All of these constructions of strike plates require a special construction of strike plate to be used in conjunction with the supporting structure, such that a simple, conventional existing strike plate cannot be used.
Accordingly it is an object of the present invention to provide a low cost, high strength securing mechanism applicable to most common frame jambs and strike plates or bolt keepers, requiring only the simplest of modification to the jamb itself. It is also an object of this invention to provide a method for strengthening the security provided by a conventional doorjamb strike plate.